out of memory, because the Buffer Menu needs a fair amount of memory
itself, and the reserve supply may not be enough.
-@cindex memory trouble, GNU/Linux
- On GNU/Linux systems, the system does not normally report running
-out of memory to Emacs, and can instead randomly kill processes when
-they run out of memory. We recommend that you turn this behavior off,
-so that Emacs can respond correctly when it runs out of memory, by
-becoming the super user, editing the file @code{/etc/sysctl.conf} to
-contain the following lines, and then running the command @code{sysctl
--p}:
+@cindex out of memory killer, GNU/Linux
+@cindex OOM killer
+ On GNU/Linux systems, Emacs does not normally get notified about
+out-of-memory situations; instead, the OS can kill the Emacs process
+when it runs out of memory. This feature is known as the
+@dfn{out-of-memory killer}, or @dfn{@acronym{OOM} killer}. When this
+behavior is in effect, Emacs is unable to detect the out-of-memory
+situation in time, and won't be able to let you save your buffer as
+described above. However, it is possible to turn off this behavior of
+the OS, and thus allow Emacs a chance to handle the out-of-memory
+situation in a more useful manner, before it is killed. To do that,
+become the super user, edit the file @code{/etc/sysctl.conf} to
+contain the lines shown below, and then invoke the command
+@w{@kbd{sysctl -p}} from the shell prompt:
@example
vm.overcommit_memory=2
vm.overcommit_ratio=0
@end example
+@noindent
+Please note that the above setting affects all the processes on the
+system, and in general the behavior of the system under memory
+pressure, not just the Emacs process alone.
+
@node Crashing
@subsection When Emacs Crashes
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